sec 7.2 Word Scramble
|
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Question | Answer |
term that describes the plasma membrane because it allows some substances to pass through while keeping others out | selectivey permeable |
the plasma membrane is an important structure for maintaining a steady state in the internal environment or | homeostasis |
What are the two major components of the plasma membrane | phospholipids and proteins |
Describe the phospholipids of a plasma membrane | a phospholipid is similar to a triglyceride except one fatty acid is replaced by a phosphate group.. making a polar head that interacts with water |
why does the phospholipid head interact with water | water is polar and the phospholipid head is polar and they like each other |
How are the phospholipids arranged in the plasma membrane | there are two layers called a phospholipid bilayer... they are arranged tail to tail ( the heads fact the exterior environment and the interior environment ( the environments are watery) |
What part of the phospholipid bilayer is farthest away from the water molecules | the nonpolar tails ( the interior portion) trys to stay away from water in the environments |
describe the barrier made by the phospholipid bilayer | the barrier is polar at its surfaces and nonpolar in the middle. Water soluble substances will not move easily through the plasma membrane... they are stopped by nonpolar middle |
There are many ? moving with and among the phospholipids | proteins |
an important protein in the plasma membrane that spans the entire membrane and makes tunnels allowing certain substances to enter and leave the cell.. | transport proteins |
where is the cholesterol of the plasma membrane located? Give a reason for this location | it is found among the phosopholipids .. the cholesterol is nonpolar and doesn't like water so it is away from the water in the middle of the membrane |
What is the function of the cholesterol in the plasma membrane? | helps prevent the fatty-acid tails of the phospholipid bilayer from sticking together.. which makes the membrane more fluid and not rigid |
Name 4 substances that is found in the plasma membrane | phospholipids, proteins, cholesterol, and carbohydrates (attached to proteins and stick out from the plasma membrane |
describe the carbohydrates in the plasma membrane | they are hooked to the proteins and stick out from the surface to the outer environment. They define the cell's characteristics and help cell's identify chemical signals |
describe the fluid mosaic model for the cell membrane | this refers to the plasma membrane and states that the phospholipids create a "sea" in which other molecules float.. and the various molecules make a pattern or mosaic on the surface.. |
Created by:
shemehl
Popular Biology sets